title: Three-dimensional distribution of polymorphs and magnesium in a calcified underwater attachment system by diffraction tomography.
abstract: Biological materials display complicated three-dimensional hierarchical structures. Determining these structures is essential in understanding the link between material design and properties. Herein, we show how diffraction tomography can be used to determine the relative placement of the calcium carbonate polymorphs calcite and aragonite in the highly mineralized holdfast system of the bivalve Anomia simplex. In addition to high fidelity and non-destructive mapping of polymorphs, we use detailed analysis of X-ray diffraction peak positions in reconstructed powder diffraction data to determine the local degree of Mg substitution in the calcite phase. These data show how diffraction tomography can provide detailed multi-length scale information on complex materials in general and of biomineralized tissues in particular.
authors.affiliation: iNANO and Department of Chemistry, Aarhus University, 14 Gustav Wieds Vej, Aarhus 8000, Denmark.
authors.forename: Hanna
authors.initials: H
authors.lastname: Leemreize
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Almer
authors.forename: Stuart R
authors.initials: SR
authors.lastname: Stock
authors.forename: Henrik
authors.initials: H
authors.lastname: Birkedal
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000737:chemistry / Q000378:metabolism*; D002113:Calcification, Physiologic / Q000502:physiology*; D002119:Calcium Carbonate / Q000737:chemistry / Q000378:metabolism*; D008274:Magnesium / Q000737:chemistry / Q000378:metabolism*; D014961:X-Ray Diffraction
chemical_list: D002119:Calcium Carbonate; D008274:Magnesium
keywords: biomineralization; calcium carbonate; diffraction tomography; hierarchical materials; magnesium substitution